[MCD] SWOMCD

Fri Jan 20 21:40:58 UTC 2006

ACUS11 KWNS 202141
SWOMCD
SPC MCD 202141 
ILZ000-MOZ000-ARZ000-202345-

MESOSCALE DISCUSSION 0075
NWS STORM PREDICTION CENTER NORMAN OK
0341 PM CST FRI JAN 20 2006

AREAS AFFECTED...PARTS OF SRN MO/NRN ARK

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 202141Z - 202345Z

AS UPPER TROUGH CONTINUES TO LIFT OUT OF THE SOUTH CENTRAL ROCKIES/
HIGH PLAINS REGION...MODELS INDICATE AN ASSOCIATE STRENGTHENING OF A
WEST SOUTHWESTERLY MID/UPPER JET STREAK WILL OCCUR ACROSS THE OZARK
PLATEAU.  THIS IS FORECAST TO OCCUR BETWEEN NOW AND LATE EVENING...
WHEN 500 MB SPEED MAX IS PROGGED TO REACH 90+ KT. 

WEAK SURFACE LOW ASSOCIATED WITH DEVELOPING SYSTEM IS ALREADY
MIGRATING INTO/ACROSS THE MISSOURI OZARKS...WITH CONVECTIVE
INITIATION ONGOING IN ZONE OF STRONGER FORCING TO THE IMMEDIATE EAST
NORTHEAST.  GIVEN MEAGER MOISTURE RETURN TO WARM SECTOR OF LOW...AND
STRONGER MID-LEVEL COOLING LAGGING TO THE WEST...INHIBITION IS STILL
TOO STRONG FOR THUNDERSTORM FORMATION. HOWEVER...IT APPEARS THIS
COULD CHANGE BY 21/00-01Z...WITH POSSIBLE NARROW BROKEN SQUALL LINE
DEVELOPING WEST SOUTHWEST OF THE ST. LOUIS/WEST PLAINS MO AND
RUSSELLVILLE AR AREAS.

CAPE IS NOT LIKELY NOT TO EXCEED A COUPLE HUNDRED J/KG...AND
POTENTIAL FOR VIGOROUS UPDRAFTS SEEMS QUITE LOW.  HOWEVER...FORECAST
SOUNDINGS SUGGEST EVAPORATIVE COOLING IN DOWNDRAFTS WILL ENHANCE
DOWNWARD MOMENTUM TRANSFER IN 40 TO 50 KT MEAN FLOW ENVIRONMENT. 
THIS COULD CONTRIBUTE TO A RISK FOR DAMAGING SURFACE GUSTS WITH
ACTIVITY AS IT SPREADS EASTWARD ACROSS THE REMAINDER OF SOUTHERN
MISSOURI/NORTHERN ARKANSAS THIS EVENING.

..KERR.. 01/20/2006

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...LSX...LZK...SGF...TSA...

37819256 38489204 39369098 38909013 37489084 36249207
35429294 35599384 36839350 

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